POS1377 LUNG INVOLVEMENT IN VEXAS SYNDROME
Authors: M. Casal Moura, M. Baqir, Y. Tandon, M. Samec, K. Reichard, A. Mangaonkar, R. Go, K. J. Warrington, M. Patnaik, M. Koster, J. H. Ryu
Journal: Annals of the Rheumatic Diseases (2022)

Background Vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome is a recently identified disorder caused by somatic mutations in the UBA1 gene of myeloid cells. Various manifestations of pulmonary involvement have been reported, but a detailed description of lung involvement and radiologic findings is lacking. Objectives To describe lung involvement in VEXAS syndrome. Methods A retrospective cohort study was conducted of all patients identified at the Mayo Clinic with VEXAS syndrome since October 2020. Clinical records and chest high resolution computed tomography (HRCT) scans were reviewed. Results Our cohort comprised 22 white men with a median age of 69 years (IQR 62-74, range 57-84). Hematologic disorders including multiple myeloma, myelodysplastic syndrome and pancytopenia were present in 10 patients (45%), rheumatologic diseases including granulomatosis with polyangiitis, IgG4-related disease, polyarteritis nodosa, relapsing polychondritis, and rheumatoid arthritis were found in 10 patients (45%), and 4 patients had dermatologic presentations including Sweet syndrome, Schnitzer-like syndrome or drug rash with eosinophilia skin syndrome (DRESS). VEXAS syndrome-related features included fever (18, 82%), skin lesions (20, 91%), lung infiltrates (12, 55%), chondritis (10, 45%), venous thromboembolism (12, 55%), macrocytic anemia (21, 96%), and bone marrow vacuoles (21, 96%). Other manifestations observed were arthritis, scleritis, hoarseness and hearing loss. Median erythrocyte sedimentation rate (ESR) was 69 mm/1 st hour (IQR 34.3-118.8) and median C-reactive protein (CRP) of 55.5 mg/dL (IQR 11.4-98.8). The somatic mutations affecting methionine-41 (p.Met41) in UBA1 gene were: 11 (50%) p.Met41Thr, 7 (32%) p.Met41Val, 2 (9%) p.Met41Leu, and 2 (9%) in the splice site. All patients received glucocorticoids (GC) (median duration of treatment was 2.6 years); 21 (96%) received conventional immunosuppressive agents (methotrexate, azathioprine, mycophenolate, leflunomide, cyclosporin, hydroxychloroquine, tofacitinib, ruxolitinib) and 9 (41%) received biologic agents (rituximab, tocilizumab, infliximab, etanercept, adalimumab, golimumab, abatacept). Respiratory symptoms included dyspnea and cough present in 21 (95%) and 12 (55%), respectively, and were documented prior to VEXAS diagnosis. Most of the patients were non-smokers (14, 64%) and obstructive sleep apnea (OSA) was present in 11 patients (50%). Seven patients (32%) used non-invasive ventilation, 6 used C-PAP, and 1 used Bi-PAP. Bronchoalveolar lavage (BAL) was available in 4 patients, and the findings were compatible with neutrophilic alveolitis in 3. Two patients had lung biopsies (2 transbronchial and 1 surgical) that showed ATTR amyloidosis and organizing pneumonia with lymphoid interstitial pneumonia, respectively. Pulmonary function tests were available in 9 (41%) patients and showed normal results in 5; 3 patients had isolated reduction in DLCO and 1 with mild restriction. On chest HRCT, 16 patients (73%) had parenchymal changes including ground-glass opacities in 9, septal thickening in 4, and nodules in 3; pleural effusions were present in 3 patients, air-trapping in 3 patients and tracheomalacia in 1 patient. Follow-up chest HRCT was available for 8 patients (36%), the ground-glass opacities resolved in 5 patients, 3 patients manifested new or increased ground-glass opacities, and 1 patient had increased interlobular septal thickening. After 1 year of follow-up, 4 patients (17%) had died; 3 due to pneumonia (2 COVID-19,1 bacterial) and 1 due to heart failure. VEXAS flares occurred in 18 patients (82%), the maximum number of relapses was 7, and they were mainly managed with GC and with changes in the immunosuppressive regimen. Conclusion Pulmonary involvement was documented by chest HRCT in most patients with VEXAS syndrome. Respiratory symptoms occurred in over one half of patients and about 20% had PFT abnormalities. The pulmonary manifestations of VEXAS are nonspecific and characterized predominantly by inflammatory parenchymal involvement. Disclosure of Interests None declared